Bed mattress with pattern



FIG. 1 is a left, front, top perspective view of a bed mattress with pattern showing our new design; and,

FIG. 2 is a top view thereof.

The short dash-short dash broken lines in the drawings depict portions of the bed mattress with pattern that form no part of the claimed design. 

CLAIM The ornamental design for a bed mattress with pattern, as shown and described. 